A new Snowden document shows that the NSA is harvesting contact lists -- e-mail address books, IM buddy lists, etc. -- from Google, Yahoo, Microsoft, Facebook, and others.
Unlike PRISM, this unnamed program collects the data from the Internet . This is similar to how the NSA identifies Tor users. They get direct access to the Internet backbone, either through secret agreements with companies like AT&T, or surreptitiously, by doing things like tapping undersea cables.